HEY THERE! Im orcyish, and this is my Second MOBAfire guide. My other can be found Here its my unorthodox Kassadin guide.

Amumu Is one of my all time, favorite champions. Hes tanky with a good amount of damage, hes fun to play, and his ult wins team fights. This is my guide on him, ( how i like to build him and why basically) Hope you enjoy :)

Above is my ideal rune setup, this section below is on alternatives

Greater Mark of Magic Penetration The only viable mark that comes to mind to get on amumu. All his attacks are magic based, so i always pick these up

Greater Seal of Armor This is my favorite seal on any tank hands down. And a must have on junglers.
Greater Seal of Scaling Mana Regeneration This rune is the only other viable seal that comes to mind, and only get this if your a non jungler, because amumu can be a bit mana dependent

Greater Glyph of Scaling Magic Resist Most games ill take this, because its generally the best tank glyph.
Greater Glyph of Scaling Ability Power Ill only take this if im building AP mumu, because of the extra damage it provide
Greater Glyph of Scaling Cooldown Reduction Ill get this ocassionally, because the more you can ult the
better.

Greater Quintessence of Health The best quint for tanks hands down, i always use these on amumu
Greater Quintessence of Magic Penetration Nice damage boost, i favor health but this is good to.
Greater Quintessence of Ability Power The AP helps alot, pick these up for early game damage.

Boots: As Amumu, you will want to pick up defensive boots, whether that's Ninja Tabi or Mercury's Treads that's situational, and up to you. Unless your building full damage for some reason, then go ahead and pick up Sorcerer's Shoes

Heart of Gold
Philosopher's Stone
Kage's lucky pick
These 3 items are a personal must have for me, it grants you an extra 15g per 10 seconds, that's HUGE. They all offer nice bonus's and easily pay for themselves.

Sunfire Aegis An amazing item to have on amumu, the damage bonus it offers is often overlooked, and this item works in perfect harmony with your Despair

Abyssal Mask Very nice item, AoE magic resist reduction, ap and some MR for yourself. one of the better AP tanky items.

Rylais crystal scepter A good chunk of health and AP, but in addition allows your abilitys to slow enemys, making them much more easy to catch.

Frozen Heart i love this item on amumu, gives you as much armor as thornmail, and reduces their attack speed. In addition it gives your ult a very nice Cooldown reduction, i always get this item on amumu.

Force of Nature Move speed, MR, and health regen, cant go wrong with that :)

Rod of Ages As a more AP based amumu i love getting this item, it gives you a huge health mana and AP boost, worth picking up early if at all for sure..

Zhonya's Hourglass This item is extremely nice to have. As the initiator you will want to take as much damage as you can handle, but if you cant handle it all ,this item will save you :)

Rabadon's Deathcap Huge AP bonus, if you want damage over survivability pick this up.

Randuin's Omen Nice survivability boost, and i like to pick this up as a support because you will be able to make sure noone can escape with this and Shurelya's Battlesong you can give your team a large advantage.

Bandage Toss This ability i max last, because while it does damage its just a gap closer ability, the stun it provides is nice though. use this to initiate then you can ult right on top of them.
Despair I get this at level 1, and max it second. Its better then tauntrum for taking down blue.
Tantrum I pick up this at level 2, and max it by 9. It does the most damage of all your basic abilitys, and lets you survive and clear the jungle faster. (It offers damage reduction also, so that hells)
Curse of the Sad Mummy This is the best ability for team fights that i can think of. Its cooldown is only about 100 seconds, it does good damage, and its basicly a instant cast 2 second AoE stun. VERY good. of course, get this at 6,11,16

Smite A must have as a jungler.

Teleport If your laning most of the time ill pick this up

Heal A nice spell, can save you

Exhaust Let another person get this, unless your not getting Rylai's Crystal Scepter

Flash <3 this spell , i always get it helps you position, and escape unlike anything else

Ignite Your not a burst champion, so you wont need this unless your against a mundo, ww or renekton etc.

Promote sucks

My jungle route.

Wolves--> Blue--> wraiths--> Wolves--> Red-->then small golems if ganking bot, wraiths if ganking mid, or wraiths--> wolves if ganking top.

Pretty standard.

Thanks for reading, im Orcyish and this was my second build. Email me at Orcyish@gmail.com with comments or suggestions, please +1 :)

~May 30 2012: Made the guide